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Abstract:

A stretchable laminate, a process of making a stretchable laminate and a
disposable absorbent article that includes a stretchable laminate are
disclosed. The stretchable laminate includes a nonwoven web and a web of
elastomeric material. The nonwoven web includes three layers of spunbond
fibers and two layers of meltblown fibers. The side of the nonwoven web
that includes two layers of spunbond fibers is attached to the
elastomeric material.

Claims:

1. A stretchable laminate comprising:a. a first nonwoven web, said first
nonwoven web comprising:i. a first layer of fibers comprising spunbond
fibers, said first layer having a top and an bottom surface;ii. a second
layer of fibers comprising meltblown fibers, said second layer having a
top and an bottom surface wherein the top surface of second third layer
of meltblown fibers faces the bottom surface of said first layer of
spunbond fibers, wherein said second layer of meltblown fibers has a
basis weight of between 0.25 g/m2 and 5 g/m2;iii. at least a
third layer of fibers comprising meltblown fibers, said third layer
having a top and a bottom surface wherein the top surface of said third
layer of meltblown fibers faces the bottom surface of said second layer
of meltblown fibers, wherein said third layer of meltblown fibers has a
basis weight of between 0.25 g/m2 and 5 g/m2;iv. a fourth layer
of fibers comprising spunbond fibers, wherein said spunbond fibers are
multi-component fibers having a core comprising a first polymer having a
first melt temperature and a sheath comprising a second polymer having a
second melt temperature wherein said second melt temperature is lower
than said first melt temperature, said fourth layer having a top and a
bottom surface, wherein the top surface of said fourth layer of spunbond
fibers faces the bottom surface of said third layer of meltblown fibers
wherein said fourth layer has a basis weight of between 1 g/m2 and
25 g/m2;v. at least a fifth layer of fibers comprising spunbond
fibers wherein said spunbond fibers are multi-component fibers having a
core comprising a first polymer having a first melt temperature and a
sheath comprising a second polymer having a second melt temperature
wherein said second melt temperature is lower than said first melt
temperature, said fifth layer having a top and a bottom surface, wherein
the top surface of said fifth layer of spunbond fibers faces the bottom
surface of said fourth layer of spunbond fibers such that said second,
third and fourth layers are positioned between said first and fifth
layers and wherein said fifth layer has a basis weight of between 1
g/m2 and 25 g/m2;and;b. a web of an elastomeric material having
top and bottom surfaces,wherein the bottom surface of said fifth layer
comprising spunbond fibers of said first nonwoven web is bonded to said
top surface of said elastomeric web to form a laminate.

2. The stretchable laminate of claim 1 wherein the spunbond fibers of said
first layer are multi-component fibers having a core comprising a first
polymer having a first melt temperature and a sheath comprising a second
polymer having a second melt temperature wherein said second melt
temperature is lower than said first melt temperature.

3. The stretchable laminate of claim 1 further comprising:c. a second
nonwoven web bonded to the bottom surface of said elastomeric web said
second nonwoven web comprising:a first layer of fibers comprising
spunbond fibers, said first layer having a top and a bottom surface;a
second layer of fibers comprising meltblown fibers, said second layer
having a top and a bottom surface wherein said bottom surface of said
second layer faces said top surface of said first layer; anda third layer
of fibers comprising spunbond fibers, said third layer having a top and a
bottom surface wherein the bottom surface of said third layer faces said
top surface of said second layer such that said second layer is
positioned between said first and third layers of said second nonwoven
web;wherein the top surface of said third layer comprising spunbond
fibers of said second nonwoven web is bonded to said bottom surface of
said elastomeric web.

4. The stretchable laminate of claim 1 wherein said elastomeric web is a
film of an elastomeric material.

5. The stretchable laminate of claim 4 wherein said film comprises an
elastomeric polyolefin.

6. The stretchable laminate of claim 1 wherein said first nonwoven web is
adhesively bonded to said elastomeric web with a hotmelt adhesive having
a melt temperature.

7. The stretchable laminate of claim 6 wherein the melt temperature of
said hotmelt adhesive is greater than the melt temperature of said second
polymer.

8. The stretchable laminate of claim 6 wherein the melt temperature of
said hotmelt adhesive is lower than the melt temperature of said first
polymer.

9. The stretchable material of claim 1 wherein at least a portion of said
laminate is mechanically activated.

10. A process of making a stretchable laminate comprising:obtaining a
first nonwoven web, said first nonwoven web comprising:a first nonwoven
web, said first nonwoven web comprising:i. a first layer of fibers
comprising spunbond fibers, said first layer having a top and an bottom
surface;ii. a second layer of fibers comprising meltblown fibers, said
second layer having a top and an bottom surface wherein the top surface
of second third layer of meltblown fibers faces the bottom surface of
said first layer of spunbond fibers, wherein said second layer of
meltblown fibers has a basis weight of between 0.25 g/m2 and 5
g/m2;iii. at least a third layer of fibers comprising meltblown
fibers, said third layer having a top and a bottom surface wherein the
top surface of said third layer of meltblown fibers faces the bottom
surface of said second layer of meltblown fibers, wherein said third
layer of meltblown fibers has a basis weight of between 0.25 g/m2
and 5 g/m2;iv. a fourth layer of fibers comprising spunbond fibers,
wherein said spunbond fibers are multi-component fibers having a core
comprising a first polymer having a first melt temperature and a sheath
comprising a second polymer having a second melt temperature wherein said
second melt temperature is lower than said first melt temperature, said
fourth layer having a top and a bottom surface, wherein the top surface
of said fourth layer of spunbond fibers faces the bottom surface of said
third layer of meltblown fibers wherein said fourth layer has a basis
weight of between 1 g/m2 and 25 g/m2;v. at least a fifth layer
of fibers comprising spunbond fibers wherein said spunbond fibers are
multi-component fibers having a core comprising a first polymer having a
first melt temperature and a sheath comprising a second polymer having a
second melt temperature wherein said second melt temperature is lower
than said first melt temperature, said fifth layer having a top and a
bottom surface, wherein the top surface of said fifth layer of spunbond
fibers faces the bottom surface of said fourth layer of spunbond fibers
such that said second, third and fourth layers are positioned between
said first and fifth layers and wherein said fifth layer has a basis
weight of between 1 g/m2 and 25 g/m2;obtaining a web of an
elastomeric material having top and bottom surfaces; andbonding said the
bottom surface of said fifth layer comprising spunbond fibers of said
first nonwoven web to said top surface of said elastomeric web.

11. The process of claim 9 further comprising:bonding a second nonwoven
web to the bottom surface of said elastomeric web wherein said second
nonwoven web comprises:a first layer of fibers comprising spunbond
fibers, said first layer having a top and a bottom surface;a second layer
of fibers comprising meltblown fibers, said second layer having a top and
a bottom surface wherein said bottom surface of said second layer faces
said top surface of said first layer; anda third layer of fibers
comprising spunbond fibers, said third layer having a top and a bottom
surface wherein the bottom surface of said third layer faces said top
surface of said first layer such that said second layer is positioned
between said first and third layers of said second nonwoven web;wherein
the top surface of said third layer comprising spunbond fibers of said
second nonwoven web is bonded to said bottom surface of said elastomeric
web.

12. The process of claim 9 wherein said elastomeric web is a film of an
elastomeric material.

13. The process of claim 12 wherein said film comprises an elastomeric
polyolefin.

14. The process of claim 9 wherein said first nonwoven web is adhesively
bonded to said elastomeric web with a hotmelt adhesive having a melt
temperature that is greater than the melt temperature of said second
polymer.

15. The process of claim 9 further comprising activating at least a
portion of said laminate.

16. A disposable absorbent article comprising:a chasis having opposing
first and second longitudinal side edges, said chassis comprising a
liquid pervious topsheet, a liquid impervious backsheet and an absorbent
core disposed between said topsheet and said backsheet; anda pair of
stretchable ears or side panels connected to each longitudinal side edge
of said chassis, each of said ears or side panels comprising a
stretchable laminate comprising:a. a first nonwoven web, said first
nonwoven web comprising:i. a first layer of fibers comprising spunbond
fibers, said first layer having a top and an bottom surface;ii. a second
layer of fibers comprising meltblown fibers, said second layer having a
top and an bottom surface wherein the top surface of second third layer
of meltblown fibers faces the bottom surface of said first layer of
spunbond fibers, wherein said second layer of meltblown fibers has a
basis weight of between 0.25 g/m2 and 5 g/m2;iii. at least a
third layer of fibers comprising meltblown fibers, said third layer
having a top and a bottom surface wherein the top surface of said third
layer of meltblown fibers faces the bottom surface of said second layer
of meltblown fibers, wherein said third layer of meltblown fibers has a
basis weight of between 0.25 g/m2 and 5 g/m2;iv. a fourth layer
of fibers comprising spunbond fibers, wherein said spunbond fibers are
multi-component fibers having a core comprising a first polymer having a
first melt temperature and a sheath comprising a second polymer having a
second melt temperature wherein said second melt temperature is lower
than said first melt temperature, said fourth layer having a top and a
bottom surface, wherein the top surface of said fourth layer of spunbond
fibers faces the bottom surface of said third layer of meltblown fibers
wherein said fourth layer has a basis weight of between 1 g/m2 and
25 g/m2;v. at least a fifth layer of fibers comprising spunbond
fibers wherein said spunbond fibers are multi-component fibers having a
core comprising a first polymer having a first melt temperature and a
sheath comprising a second polymer having a second melt temperature
wherein said second melt temperature is lower than said first melt
temperature, said fifth layer having a top and a bottom surface, wherein
the top surface of said fifth layer of spunbond fibers faces the bottom
surface of said fourth layer of spunbond fibers such that said second,
third and fourth layers are positioned between said first and fifth
layers and wherein said fifth layer has a basis weight of between 1
g/m2 and 25 g/m2;and;b. a web of an elastomeric material having
top and bottom surfaces,wherein the bottom surface of said fifth layer
comprising spunbond fibers of said first nonwoven web is bonded to said
top surface of said elastomeric web to form a laminate.

17. The absorbent article of claim 16 wherein said elastomeric web is a
film comprising an elastomeric polyolefin.

18. The absorbent article of claim 16 further comprising:c. a second
nonwoven web bonded to the bottom surface of said elastomeric web wherein
said second nonwoven web comprises:a first layer of fibers comprising
spunbond fibers, said first layer having a top and a bottom surface;a
second layer of fibers comprising meltblown fibers, said second layer
having a top and a bottom surface wherein said bottom surface of said
second layer faces said top surface of said first layer; anda third layer
of fibers comprising spunbond fibers, said third layer having a top and a
bottom surface wherein the bottom surface of said third layer faces said
top surface of said second layer such that said second layer is
positioned between said first and third layers of said second nonwoven
web;wherein the top surface of said third layer comprising spunbond
fibers of said second nonwoven web is bonded to said bottom surface of
said elastomeric web.

19. The disposable absorbent article of claim 18 wherein said spunbond
fibers of said first and third layers of said second nonwoven web are
multi-component fibers having a core comprising a first polymer having a
first melt temperature and a sheath comprising a second polymer having a
second melt temperature wherein said second melt temperature is lower
than said first melt temperature and wherein each of said first and third
layers of said second nonwoven web has a basis weight of between 1
g/m2 and 25 g/m2;

20. The disposable absorbent article of claim 16 wherein at least a
portion of said stretchable laminate is activated.

Description:

CROSS REFERENCE TO RELATED APPLICATION

[0001]This application claims the benefit of U.S. Provisional Application
No. 61/167,633, filed Apr. 8, 2009, the substance of which is
incorporated herein by reference.

FIELD OF THE INVENTION

[0002]The disclosure generally relates to stretchable laminates of
nonwoven web(s) and a film that may be an elastic film. The disclosure
also relates to processes of making such stretchable laminates and
articles incorporating such stretchable laminates.

BACKGROUND OF THE INVENTION

[0003]Stretchable laminates that include at least a nonwoven fibrous web
bonded to an elastic film are well known in the art. These laminates are
particularly useful when used to make at least one of the numerous
elements that ultimately form disposable absorbent articles such as
diapers, pants and adult incontinence products. For example, stretchable
laminates may be used to make stretchable elements such as stretchable
ears, stretchable side panels or a stretchable outer cover for an
absorbent article. Among other benefits, these stretchable elements
provide a better fit of the absorbent article on the user. A typical
stretchable laminate that includes a fibrous nonwoven web bonded to an
elastic film may be relatively hard to elongate by a caregiver or a user
unless the laminate as been mechanically "activated." During mechanical
activation, the stretchable laminate is strained to allow the laminate to
at least partially recover some of the ease of elongation that the
elastic film had before its bonding to the nonwoven web. Some nonwoven
webs, such as webs made of carded staple fibers, are easily stretchable
or elongatable even when bonded to an elastic film. During mechanical
activation, carded webs offer relatively little resistance and, as a
result, a stretchable laminate that includes such carded webs can be
pre-strained to a great extent without causing either the carded web or
the elastic film to tear completely. The main drawback of carded webs is
their cost in comparison to other nonwoven webs such as webs that include
a layer of spunbond fibers. The relatively inexpensive manufacturing
process used to make spunbond type nonwoven webs can make them
particularly attractive for use in a stretchable laminate but these webs
tend to be much more difficult to elongate without causing the spunbond
web and/or the elastic film to tear during the mechanical activation of
the laminate. Due to their manufacturing process, spunbond webs may also
have local variations in their basis weight that can cause the spunbond
web and the elastic film to tear during mechanical activation. A
stretchable laminate whose elastic film is torn cannot be used and must
be discarded causing undesirable waste and expenses. A stretchable
laminate whose nonwoven web is repeatedly torn may be unpleasant to the
touch when the laminate is elongated by a caregiver or a user. A nonwoven
web that is partially or completely torn offers little or no resistance
to limit the elongation of the overall stretchable laminate which in turn
may potentially lead to the failure of the stretchable element made of
the laminate if a caregiver or user elongates the elements abusively.

[0004]It is therefore an object of the invention to provide a stretchable
laminate that includes a spunbond nonwoven web bonded to an elastic film
to form a laminate that is able to endure mechanical activation without
causing the spunbond nonwoven web or the elastic film to tear. It is also
an object of the invention to provide a process for making such a
stretchable laminate. It is still an object of the invention to provide
an article having at least one element that includes such a stretchable
laminate.

[0005]It is believed that at least some of the objects of the invention
can be accomplished by stretchable laminates that include a nonwoven web
having a spunbond layer made of bi-component fibers of a certain type. It
is also believed that at least some of the objects of the invention can
be accomplished by stretchable laminates that include a nonwoven web
having a spunbond layer having a more uniform basis weight.

SUMMARY OF THE INVENTION

[0006]In one embodiment, the invention is directed to a stretchable
laminate that comprises: [0007]a. a first nonwoven web, said first
nonwoven web comprising:

[0008]i. a first layer of fibers comprising spunbond fibers, said first
layer having a top and an bottom surface;

[0009]ii. a second layer of fibers comprising meltblown fibers, said
second layer having a top and an bottom surface wherein the top surface
of second third layer of meltblown fibers faces the bottom surface of
said first layer of spunbond fibers, wherein said second layer of
meltblown fibers has a basis weight of between 0.25 g/m2 and 5
g/m2;

[0010]iii. at least a third layer of fibers comprising meltblown fibers,
said third layer having a top and a bottom surface wherein the top
surface of said third layer of meltblown fibers faces the bottom surface
of said second layer of meltblown fibers, wherein said third layer of
meltblown fibers has a basis weight of between 0.25 g/m2 and 5
g/m2;

[0011]iv. a fourth layer of fibers comprising spunbond fibers, wherein
said spunbond fibers are multi-component fibers having a core comprising
a first polymer having a first melt temperature and a sheath comprising a
second polymer having a second melt temperature wherein said second melt
temperature is lower than said first melt temperature, said fourth layer
having a top and a bottom surface, wherein the top surface of said fourth
layer of spunbond fibers faces the bottom surface of said third layer of
meltblown fibers wherein said fourth layer has a basis weight of between
1 g/m2 and 25 g/m2;

[0012]v. at least a fifth layer of fibers comprising spunbond fibers
wherein said spunbond fibers are multi-component fibers having a core
comprising a first polymer having a first melt temperature and a sheath
comprising a second polymer having a second melt temperature wherein said
second melt temperature is lower than said first melt temperature, said
fifth layer having a top and a bottom surface, wherein the top surface of
said fifth layer of spunbond fibers faces the bottom surface of said
fourth layer of spunbond fibers such that said second, third and fourth
layers are positioned between said first and fifth layers and wherein
said fifth layer has a basis weight of between 1 g/m2 and 25
g/m2; [0013]and; [0014]b. a web of an elastomeric material having
top and bottom surfaces, [0015]wherein the bottom surface of said fifth
layer comprising spunbond fibers of said first nonwoven web is bonded to
said top surface of said elastomeric web to form a laminate.

[0016]In another embodiment, the invention is directed to a process of
making a stretchable laminate that comprises: [0017]obtaining a first
nonwoven web, said first nonwoven web comprising: [0018]a first nonwoven
web, said first nonwoven web comprising:

[0019]i. a first layer of fibers comprising spunbond fibers, said first
layer having a top and an bottom surface;

[0020]ii. a second layer of fibers comprising meltblown fibers, said
second layer having a top and an bottom surface wherein the top surface
of second third layer of meltblown fibers faces the bottom surface of
said first layer of spunbond fibers, wherein said second layer of
meltblown fibers has a basis weight of between 0.25 g/m2 and 5
g/m2;

[0021]iii. at least a third layer of fibers comprising meltblown fibers,
said third layer having a top and a bottom surface wherein the top
surface of said third layer of meltblown fibers faces the bottom surface
of said second layer of meltblown fibers, wherein said third layer of
meltblown fibers has a basis weight of between 0.25 g/m2 and 5
g/m2;

[0022]iv. a fourth layer of fibers comprising spunbond fibers, wherein
said spunbond fibers are multi-component fibers having a core comprising
a first polymer having a first melt temperature and a sheath comprising a
second polymer having a second melt temperature wherein said second melt
temperature is lower than said first melt temperature, said fourth layer
having a top and a bottom surface, wherein the top surface of said fourth
layer of spunbond fibers faces the bottom surface of said third layer of
meltblown fibers wherein said fourth layer has a basis weight of between
1 g/m2 and 25 g/m2;

[0023]v. at least a fifth layer of fibers comprising spunbond fibers
wherein said spunbond fibers are multi-component fibers having a core
comprising a first polymer having a first melt temperature and a sheath
comprising a second polymer having a second melt temperature wherein said
second melt temperature is lower than said first melt temperature, said
fifth layer having a top and a bottom surface, wherein the top surface of
said fifth layer of spunbond fibers faces the bottom surface of said
fourth layer of spunbond fibers such that said second, third and fourth
layers are positioned between said first and fifth layers and wherein
said fifth layer has a basis weight of between 1 g/m2 and 25
g/m2; [0024]obtaining a web of an elastomeric material having top
and bottom surfaces; and [0025]bonding said the bottom surface of said
fifth layer comprising spunbond fibers of said first nonwoven web to said
top surface of said elastomeric web.

[0026]In another embodiment, the invention is directed to a disposable
absorbent article that comprises: [0027]a chasis having opposing first
and second longitudinal side edges, said chassis comprising a liquid
pervious topsheet, a liquid impervious backsheet and an absorbent core
disposed between said topsheet and said backsheet; and [0028]a pair of
stretchable ears or side panels connected to each longitudinal side edge
of said chassis, each of said ears or side panels comprising a
stretchable laminate comprising: [0029]a. a first nonwoven web, said
first nonwoven web comprising:

[0030]i. a first layer of fibers comprising spunbond fibers, said first
layer having a top and an bottom surface;

[0031]ii. a second layer of fibers comprising meltblown fibers, said
second layer having a top and an bottom surface wherein the top surface
of second third layer of meltblown fibers faces the bottom surface of
said first layer of spunbond fibers, wherein said second layer of
meltblown fibers has a basis weight of between 0.25 g/m2 and 5
g/m2;

[0032]iii. at least a third layer of fibers comprising meltblown fibers,
said third layer having a top and a bottom surface wherein the top
surface of said third layer of meltblown fibers faces the bottom surface
of said second layer of meltblown fibers, wherein said third layer of
meltblown fibers has a basis weight of between 0.25 g/m2 and 5
g/m2;

[0033]iv. a fourth layer of fibers comprising spunbond fibers, wherein
said spunbond fibers are multi-component fibers having a core comprising
a first polymer having a first melt temperature and a sheath comprising a
second polymer having a second melt temperature wherein said second melt
temperature is lower than said first melt temperature, said fourth layer
having a top and a bottom surface, wherein the top surface of said fourth
layer of spunbond fibers faces the bottom surface of said third layer of
meltblown fibers wherein said fourth layer has a basis weight of between
1 g/m2 and 25 g/m2;

[0034]v. at least a fifth layer of fibers comprising spunbond fibers
wherein said spunbond fibers are multi-component fibers having a core
comprising a first polymer having a first melt temperature and a sheath
comprising a second polymer having a second melt temperature wherein said
second melt temperature is lower than said first melt temperature, said
fifth layer having a top and a bottom surface, wherein the top surface of
said fifth layer of spunbond fibers faces the bottom surface of said
fourth layer of spunbond fibers such that said second, third and fourth
layers are positioned between said first and fifth layers and wherein
said fifth layer has a basis weight of between 1 g/m2 and 25
g/m2; [0035]and; [0036]b. a web of an elastomeric material having
top and bottom surfaces, [0037]wherein the bottom surface of said fifth
layer comprising spunbond fibers of said first nonwoven web is bonded to
said top surface of said elastomeric web to form a laminate.

BRIEF DESCRIPTION OF THE DRAWINGS

[0038]FIG. 1 is a schematic cross-sectional view of a stretchable laminate
in accordance with an embodiment of the invention;

[0039]FIG. 2 is a schematic cross-sectional view of a stretchable laminate
in accordance with another embodiment of the invention;

[0040]FIG. 3 is a schematic cross-sectional view of a stretchable laminate
in accordance with another embodiment of the invention;

[0041]FIG. 4 is a schematic cross-sectional view of a bi-component fiber
in accordance with an embodiment of the invention;

[0042]FIG. 5A is a schematic representation of a nonwoven web
manufacturing process;

[0043]FIG. 5B is a schematic representation of a pattern of thermo-bonds
formed on a nonwoven web;

[0044]FIG. 6 is a photograph of a stretchable laminate before mechanical
activation;

[0045]FIG. 7 is a photograph of a stretchable laminate after mechanical
activation;

[0046]FIG. 8 is a magnified photograph of a bond site of a stretchable
laminate after mechanical activation;

[0047]FIG. 9 is a photograph of a stretchable laminate in accordance with
an embodiment of the invention before mechanical activation of the
laminate;

[0048]FIG. 10 is a photograph of a stretchable laminate in accordance with
an embodiment of the invention after mechanical activation of the
laminate;

[0049]FIG. 11 is magnified photograph of a bond site of a stretchable
laminate in accordance with an embodiment of the invention after
mechanical activation of the laminate;

[0050]FIG. 12 represents tensile curves for various nonwoven webs;

[0051]FIGS. 13A-13E are photographs of various webs after mechanical
activation of a laminate that are delaminated from the laminate;

[0054]FIG. 16 is a schematic representation of a device for mechanically
activating a stretchable laminate;

[0055]FIG. 17 is a schematic cross-sectional view of a device for
mechanically activating a stretchable laminate;

[0056]FIG. 18 is a schematic representation of a disposable absorbent
article; and

[0057]FIG. 19 is a schematic cross-sectional representation of a
disposable absorbent article.

DETAILED DESCRIPTION OF THE INVENTION

[0058]As used herein, the term "activated" refers to a material which has
been mechanically deformed in order to increase the extensibility of at
least a portion of the material. A material may be activated by, for
example, incrementally stretching the material in at least one direction.

[0059]As used herein, the terms "carded staple fibers" refer to fibers
that are of a discrete length which are sorted, separated, and at least
partially aligned by a carding process. For example, a carded web refers
to a web that is made from fibers which are sent through a combing or
carding unit, which separates or breaks apart and aligns the fibers in,
e.g., the machine direction to form a generally machine
direction-oriented fibrous non-woven web. Carded staple fibers may or may
not be bonded after being carded.

[0060]As used herein, the terms "elongatable material" "extensible
material" or "stretchable material" are used interchangeably and refer to
a material that, upon application of a biasing force, can stretch to an
elongated length of at least 150% of its relaxed, original length (i.e.
can stretch to 50% more than its original length), without complete
rupture or breakage as measured by Tensile Test described in greater
detail below. In the event such an elongatable material recovers at least
40% of its elongation upon release of the applied force, the elongatable
material will be considered to be "elastic" or "elastomeric." For
example, an elastic material that has an initial length of 100 mm can
extend at least to 150 mm, and upon removal of the force retracts to a
length of at least 130 mm (i.e., exhibiting a 40% recovery). In the event
the material recovers less than 40% of its elongation upon release of the
applied force, the elongatable material will be considered to be
"substantially non-elastic" or "substantially non-elastomeric. For
example, an elastic material that has an initial length of 100 mm can
extend at least to 150 mm, and upon removal of the force retracts to a
length of at least 145 mm (i.e., exhibiting a 10% recovery).

[0061]As used herein, the term "film" refers generally to a relatively
nonporous material made by a process that includes extrusion of, e.g., a
polymeric material through a relatively narrow slot of a die. The film
may be impervious to a liquid and pervious to an air vapor, but need not
necessarily be so. Suitable examples of film materials are described in
more detail herinbelow.

[0062]As used herein, the term "layer" refers to a sub-component or
element of a web. A "layer" may be in the form of a plurality of fibers
made from a single beam on a multibeam nonwoven machine (for example a
spunbond/meltblown/spunbond nonwoven web includes at least one layer of
spunbond fibers, at least one layer of meltblown fibers and at least one
layer of spunbond fibers) or in the form of a film extruded or blown from
a single die.

[0063]As used herein, the term "machine direction" or "MD" is the
direction that is substantially parallel to the direction of travel of a
web as it is made. Directions within 45 degrees of the MD are considered
to be machine directional. The "cross direction" or "CD" is the direction
substantially perpendicular to the MD and in the plane generally defined
by the web. Directions within 45 degrees of the CD are considered to be
cross directional.

[0064]As used herein, the term "meltblown fibers" refers to fibers made
via a process whereby a molten material (typically a polymer), is
extruded under pressure through orifices in a spinneret or die. High
velocity hot air impinges upon and entrains the filaments as they exit
the die to form filaments that are elongated and reduced in diameter and
are fractured so that fibers of generally variable but mostly finite
lengths are produced. This differs from a spunbond process whereby the
continuity of the filaments is preserved along their length. An exemplary
meltblown process may be found in U.S. Pat. No. 3,849,241 to Buntin et
al.

[0065]As used herein, the term "nonwoven" means a porous, fibrous material
made from continuous (long) filaments (fibers) and/or discontinuous
(short) filaments (fibers) by processes such as, for example,
spunbonding, meltblowing, carding, and the like. Nonwoven webs do not
have a woven or knitted filament pattern.

[0066]As used herein, the term "spunbond fibers" refers to fibers made via
a process involving extruding a molten thermoplastic material as
filaments from a plurality of fine, typically circular, capillaries of a
spinneret, with the filaments then being attenuated by applying a draw
tension and drawn mechanically or pneumatically (e.g., mechanically
wrapping the filaments around a draw roll or entraining the filaments in
an air stream). The filaments may be quenched by an air stream prior to
or while being drawn. The continuity of the filaments is typically
preserved in a spundbond process. The filaments may be deposited on a
collecting surface to form a web of randomly arranged substantially
continuous filaments, which can thereafter be bonded together to form a
coherent nonwoven fabric. Exemplary spunbond process and/or webs formed
thereby may be found in U.S. Pat. Nos. 3,338,992; 3,692,613, 3,802,817;
4,405,297 and 5,665,300.

[0067]As used herein, the term "web" refers to an element that includes at
least a fibrous layer or at least a film layer and has enough integrity
to be rolled, shipped and subsequently processed (for example a roll of a
web may be unrolled, pulled, taught, folded and/or cut during the
manufacturing process of an article having an element that includes a
piece of the web). Multiple layers may be bonded together to form a web.

[0068]While not intending to limit the utility of the stretchable laminate
described herein, it is believed that a brief description of its
characteristics as they may relate to the laminate manufacturing and
intended use will help elucidate the invention. In heretofore stretchable
laminates suitable for use, for example, as an element of an absorbent
article, the laminates typically comprise at least a nonwoven web that is
bonded to an elastic film. Modern absorbent articles such as diaper,
pants or adult incontinence products include many elements that are at
one time or another in contact with the caregiver or user's skin. The use
of nonwoven materials is particularly advantageous in such elements due
to the soft feel and their cloth-like appearance they provide. Modern
disposable absorbent articles are also designed to provide an
underwear-like fit. Some of the elements of modern absorbent articles are
provided with elastic components which provide them with elastic
properties and contribute not only to the performance but also the
underwear-like fit of these absorbent articles when worn by a user.
Non-limiting examples of such elements that include elastic components
include ear panels of a diaper, side panels of a pant or at least part if
not all of the outer cover. Known stretchable laminates typically include
at least a nonwoven web that is bonded to an elastic film. The laminate
is then mechanically activated to at least partially recover some of the
ease of elongation that the elastic film had prior to being bonded to the
nonwoven web. Mechanical activation of the stretchable laminate is often
achieved by passing at least a portion of the laminate between a pair of
pressure applicators having three-dimensional surfaces which at least to
a degree are complementary to one another as disclosed, for example, in
U.S. Pat. No. 5,167,897 to Weber et al., issued Dec. 1, 1992 and assigned
to The Procter and Gamble Company. Typical stretchable laminates include
an elastic film and two separate nonwoven webs that are respectively
bonded on each side of the elastic film. Known nonwoven webs that have
been used to make stretchable laminates are nonwoven webs made of carded
staple fibers and nonwoven webs that include one or more layers of
spunbond fibers such as a spunbond/meltblow/spunbond web. These carded or
spunbond webs are made of mono-component fibers that are typically made
of polypropylene. During mechanical activation, a carded web offers
relatively little resistance to its elongation and, as a result, a
stretchable laminate that includes such a carded web may be pre-strained
or activated to a great extent without causing either the carded web or
the elastic film to tear completely. However, carded webs can be rather
costly in comparison to spunbond webs. On the other hand, spunbond webs
tend to be much more difficult to elongate without causing the spunbond
web and/or the elastic web to tear during the mechanical activation of
the laminate. Since manufacturers of absorbent articles are under
continuous pressure to reduce manufacturing cost and minimize
manufacturing waste, it is believed that the stretchable laminate
disclosed hereinafter may be a suitable alternative to already existing
stretchable laminates. The foregoing considerations are addressed by the
present invention, as will be clear from the detailed disclosures which
follow.

[0069]Reference will now be made in detail to the present preferred
embodiments of the invention, examples of which are illustrated in the
accompanying drawings wherein like numerals indicate the same elements
throughout the views and wherein reference numerals having the same last
two digits (e.g., 20 and 120) connote similar elements.

[0070]In one embodiment of the invention schematically represented in FIG.
1, a stretchable laminate 10 comprises a nonwoven web 20 that is bonded
to an elastic web 30 which form together a bi-laminate. The nonwoven web
20 comprises at least one layer 120 of spunbond fibers having top and
bottom surface such that the bottom surface of the layer 120 is bonded to
top surface or side of the elastic web 30 via an adhesive. The nonwoven
web 20 may comprise additional layers such as for example at least one
layer 220 of meltblown fibers (having top and bottom surfaces) and at
least one layer 320 of spunbond fibers (also having top and bottom
surfaces). The top surface of layer 220 faces the bottom surface of layer
320 and the top surface of layer 120 faces the bottom surface of layer
220. The layer 120 of spunbond fibers may have a basis weight of between
2 g/m2 and 50 g/m2, between 4 g/m2 and 25 g/m2 or
even between 5 g/m2 and 20 g/m2. The layer 220 of meltblown
fibers that may have a basis weight of between 0.5 g/m2 and 10
g/m2, between 0.5 g/m2 and 8 g/m2 or even between 1
g/m2 and 5 g/m2. The layer 320 of spunbond fibers may have a
basis weight of between 2 g/m2 and 50 g/m2, between 4 g/m2
and 25 g/m2 or even between 5 g/m2 and 20 g/m2. The basis
weight of any of the webs described herein may be determined using
European Disposables and Nonwovens Association ("EDANA") method 40.3-90.
The basis weight of any of the individual layers described herein, and
which together form a web, may be determined by running in sequence each
of the fiber forming beams that are used to form separate layers and then
measuring the basis weight of the consecutive formed layer(s) according
to EDANA method 40.3-90. By way of example, the basis weight of each of
the layers of an spunbond/meltblown/spunbond web (comprising a first
layer of spunbond fibers, a layer of meltblown fibers and a second layer
of spunbond fibers) can be determined by first forming the first layer of
spunbond fibers without forming the layer of meltblown fibers nor the
second layer of spunbond fibers. The nonwoven that is produced includes
only the first layer of spunbond fibers and its basis weight can be
determined according to EDANA method 40.3-90. The basis weight of the
layer of meltblown fibers can be determined by forming the first layer of
spunbond fibers under the same conditions as in the previous step
followed by formation of the layer of meltblown fibers laid on top of the
first layer of spunbond fibers. The aggregate basis weight of the
spunbond/meltblown web (which is again formed of the first layer of
spundbond fibers and the layer of meltblown fibers) can be determined
according to EDANA method 40.3-90. Since the basis weight of the first
layer of spunbond fibers is known, the basis weight of the layer of
meltblown fibers can be determined by subtracting the value of the basis
weight of the first layer of spunbond fibers from the value of the
aggregate basis weight of the spunbond/meltblown web. The basis weight of
the second layer of spunbond fibers can be determined by forming the
first layer of spunbond fibers and the layer of meltblown fibers under
the same conditions as in the previous step followed by the formation of
the second layer of spunbond fibers laid on top of the layer of meltblown
fibers. The aggregate basis weight of the spunbond/meltblown/spunbond web
can be determined according to EDANA method 40.3-90. Since the basis
weight of the spunbond/meltblown web is known, the basis weight of the
second layer of spunbond fibers can be determined by subtracting the
value of the aggregate basis weight of the spunbond/meltblown web from
the value of the aggregate basis weight of the
spunbond/meltblown/spunbond web. The foregoing steps used to determine
the basis weight of individual layers forming a web can be applied on as
many layers as the ultimate nonwoven web includes. As previously
discussed, the aggregate basis weight of the nonwoven web 20 is equal to
the sum of the basis weight of each of its individual layers. In one
embodiment represented in FIG. 2, it can be advantageous to provide the
nonwoven web 20 with at least two layers 1120, 2120 of spunbond fibers
(each having top and bottom surfaces) in the portion of the web 20 that
is disposed on the elastomeric web facing portion of the nonwoven web 20
(i.e. the portion of the nonwoven web located between the layer 220 of
meltblown fibers and the elastic web 30) instead of a single layer 120 of
spunbond fibers. It is believed that the at least two separate layers of
spunbond fibers may have a combined basis weight equal to the basis
weight of the layer 120 of spunbond fibers and provide a greater level of
performance than this single layer 120 during activation of at least a
portion of the stretchable laminate. It is also believed that the at
least two separate layers of spunbond fibers may have a combined basis
weight that is less than the basis weight of a single layer 120 of
spunbond fibers and provide the same level of performance as the single
layer 120. By way of example, each of the layers of spunbond fibers 1120
and 2120 may have a basis weight of 6 g/m2 as opposed to a single
layer of spunbond fibers having a basis weight of at least 12 g/m2.
Each of the layers 1120 and 2120 of spunbond fibers may have a basis
weight of between 1 g/m2 and 25 g/m2, between 2 g/m2 and
12.5 g/m2 or even between 2.5 g/m2 and 10 g/m2. It is
believed that at least two separate layers of spunbond fibers provide
greater basis weight homogeneity to the nonwoven web 20 and in particular
to the elastomeric web facing portion of the nonwoven web 20. Without
intending to be bound by any theory, it is also believed that since the
elastomeric web facing portion of the nonwoven web 20 is the portion of
the web that is directly bonded to the elastomeric web, a more
homogeneous basis weight may help prevent local micro-tearing of the
nonwoven web 20 during mechanical activation which may propagate to the
elastomeric web and cause the elastomeric web 30 to tear. It is believed
that local micro-tearing of the nonwoven web during mechanical activation
may lead to an over-elongation of the portion of the elastomeric web that
is in the immediate vicinity of the micro-tear formed on the nonwoven
web. This over-elongation of the elastomeric web may result in the
elastomeric web being torn or ruptured, in particular when the
elastomeric web is a film. It should be understood that the elastomeric
web facing portion of the nonwoven web 20 may include more than two
layers of spunbond fibers with an even lower basis weight to provide an
even greater homogeneity.

[0071]In one embodiment, it can also be advantageous to provide the
nonwoven web 20 with at least two layers 1220, 2220 of meltblown fibers
(each having top and bottom surfaces) in the central portion of the web
20 instead of a single the layer 220 of meltblown fibers. The at least
two separate layers 1220, 2220 of meltblown fibers may have a combined
basis weight equal to the basis weight of the layer 220 of meltblown
fibers and provide a greater level of performance than this single layer
120. In the alternative, the at least two separate layers of meltblown
fibers may have a combined basis weight that is less than the basis
weight of a single layer 220 of meltblown fibers and provide the same
level of performance as the single layer 220. By way of example, each of
the layers of meltblown fibers 1220 and 2220 may have a basis weight of 1
g/m2 as opposed to a single layer of meltblown fibers having a basis
weight of at least 2 g/m2. Each of the layers 1220 and 2220 of
meltblown fibers may have a basis weight of between 0.25 g/m2 and 5
g/m2, between 0.25 g/m2 and 4 g/m2 or even between 0.5
g/m2 and 2.5 g/m2. A layer 220 of meltblown fibers may be
particularly advantageous when the layer 120 or layers 1120, 2120 of
spunbond fibers disposed in the elastomeric web facing portion of the web
20 are adhesively bonded to the elastomeric web 30 with for example a
hotmelt adhesive (schematically represented by round dots 15 in FIGS. 1
and 2). It is believed that a meltblown layer 220 may prevent the
adhesive from reaching and even "bleeding though" the layer of spunbond
fibers 320 which is the layer that may be in contact with the caregiver
or user's skin. It is believed that two separate layers of meltblown
fibers having a low basis weight are more effective at preventing
adhesive "bleed-through" than a single layer of meltblown fibers having a
higher basis weight. It is also believed that a layer 220 of meltblown
fibers may conveniently be used as a "carrier layer" for additional
smaller fibers such as nanofibers (i.e. fibers having a diameter of less
than 1 nm). It is further believed that a layer 220 of meltblown fibers
having a homogeneous basis weight may help achieve a more uniform
coverage of any coating applied to the nonwoven web such as an adhesive
coating, a printed ink, a surfactant and/or a softening agent. It should
be understood that the central portion (i.e. the portion of the web
disposed between the outer layers of the web) of the nonwoven web 20 may
include more than two layers 1220, 2220 of meltblown fibers with an even
lower basis weight in order to provide an even greater homogeneity. One
of ordinary skill will also appreciate that although the production of
each of the layers 1120, 2120 of spunbond fibers and each or the layers
1220 and 2220 may require separate beams, it is believed that the
production throughput of the nonwoven web may be increased. In the
embodiment represented in FIG. 2, the top surface of layer 1120 faces the
bottom surface of layer 2120, the top surface of layer 2120 faces the
bottom surface of layer 1220, the top surface of layer 1220 faces the
bottom surface of layer 2220 and the top surface of layer 2220 faces the
bottom surface of layer 320,

[0072]In one embodiment, it can be also advantageous to provide the
nonwoven web 20 with at least two layers of spunbond fibers in the
portion of the web 20 that is facing away from the elastic web 30 (i.e.
the portion of the nonwoven web positioned on top of the layer 220 of
meltblown fibers) instead of a single the layer 320 of spunbond fibers.

[0073]In one embodiment, the elastomeric web 30 may be an elastomeric
nonwoven web or an elastomeric film. The elastic web 30 in the form of a
film may include a core layer 130 made of an elastomeric material that
may be directly bonded to the spunbond layer 120 of the nonwoven web 20.
A core layer 130 can be directly bonded to the nonwoven web 20 by
extruding an elastomeric material directly onto a nonwoven web. An
adhesive may be added onto the contact surface of the extruded
elastomeric material to increase the bond strength between the
elastomeric web and the nonwoven web. Non-limiting examples of suitable
elastomeric materials include thermoplastic elastomers chosen from at
least one of styrenic block copolymers, metallocene-catalyzed
polyolefins, polyesters, polyurethanes, polyether amides, and
combinations thereof. Suitable styrenic block copolymers may be diblock,
triblock, tetrablock, or other multi-block copolymers having at least one
styrenic block. Exemplary styrenic block copolymers include
styrene-butadiene-styrene, styrene-isoprene-styrene,
styrene-ethylene/butylenes-styrene, styrene-ethylene/propylene-styrene,
and the like. Commercially available styrenic block copolymers include
KRATON® from the Shell Chemical Company of Houston, Tex.; SEPTON®
from Kuraray America, Inc. of New York, N.Y.; and VECTOR® from Dexco
Chemical Company of Houston, Tex. Commercially available
metallocene-catalyzed polyolefins include EXXPOL® and EXACT® from
Exxon Chemical Company of Baytown, Tex.; AFFINITY® and ENGAGE®
from Dow Chemical Company of Midland, Mich. Commercially available
polyurethanes include ESTANE® from Noveon, Inc., Cleveland, Ohio.
Commercial available polyether amides include PEBAX® from Atofina
Chemicals of Philadelphia, Pa. Commercially available polyesters include
HYTREL® from E. I. DuPont de Nemours Co., of Wilmington, Del. Other
particularly suitable examples of elastomeric materials include
elastomeric polypropylenes. In these materials, propylene represents the
majority component of the polymeric backbone, and as a result, any
residual crystallinity possesses the characteristics of polypropylene
crystals. Residual crystalline entities embedded in the propylene-based
elastomeric molecular network may function as physical crosslinks,
providing polymeric chain anchoring capabilities that improve the
mechanical properties of the elastic network, such as high recovery, low
set and low force relaxation. Suitable examples of elastomeric
polypropylenes include an elastic random poly(propylene/olefin)
copolymer, an isotactic polypropylene containing stereoerrors, an
isotactic/atactic polypropylene block copolymer, an isotactic
polypropylene/random poly(propylene/olefin) copolymer block copolymer, a
reactor blend polypropylene, a very low density polypropylene (or,
equivalently, ultra low density polypropylene), a metallocene
polypropylene, and combinations thereof. Suitable polypropylene polymers
including crystalline isotactic blocks and amorphous atactic blocks are
described, for example, in U.S. Pat. Nos. 6,559,262, 6,518,378, and
6,169,151. Suitable isotactic polypropylene with stereoerrors along the
polymer chain are described in U.S. Pat. No. 6,555,643 and EP 1 256 594
A1. Suitable examples include elastomeric random copolymers (RCPs)
including propylene with a low level comonomer (e.g., ethylene or a
higher a-olefin) incorporated into the backbone. Suitable elastomeric RCP
materials are available under the names VISTAMAXX (available from
ExxonMobil, Houston, Tex.) and VERSIFY (available from Dow Chemical,
Midland, Mich.).

[0074]It will be appreciated that elastomeric materials that are typically
used to form an elastic film may be tacky and cause the elastic film to
stick to itself in the event the elastic film is rolled. It may be
beneficial to provide at least one of the surfaces or sides of the core
layer 130 with at least a skin layer 230 made of a material that does not
stick to itself. Non-limiting examples of suitable materials for use as a
skin layer include polyolefins such as polyethylene. Among other
benefits, a skin layer 230 allows the elastic film 30 to be rolled for
shipping and later unrolled for further processing. In one embodiment,
the elastic film 30 may include a second skin layer disposed on the other
surface or side of the core layer 130. The elastic film web may have a
basis weight of between 10 g/m2 and 150 g/m2, between 15
g/m2 and 100 g/m2 or even between 20 g/m2 and 70
g/m2. The core layer 130 of the elastic film may have a basis weight
of between 10 g/m2 and 150 g/m2, between 15 g/m2 and 100
g/m2 or even between 20 g/m2 and 70 g/m2 and the skin
layer 230 (if present) may have a basis weight of between 0.25 g/m2
and 15 g/m2, between 0.5 g/m2 and 10 g/m2 or even between
1 g/m2 and 7 g/m2.

[0075]In one embodiment schematically represented in FIG. 3, the
stretchable laminate previously discussed in the context of FIG. 2 may
additionally comprise a second nonwoven web 40 bonded to the other
surface or side of the elastic film 30. The second nonwoven web 40 may be
a web of carded staple fibers or in the alternative a web comprising at
least one layer of spunbond and/or meltblown fibers. In one embodiment,
the second nonwoven web 40 can include any of the layers previously
discussed in the context of the nonwoven web 20 (i.e. nonwoven layers
identified by reference numerals 140, 240, 340, 1140, 2140, 1240 and
2240). Consequently, the elastomeric web facing portion of the second
nonwoven web 40 can include one (140), two (1140, 2140) or more layers of
spunbond fibers. The central portion of the second nonwoven web 40 can
include one (240), two (1240, 2240) or more layers of meltblown fibers.
In one embodiment, the nonwoven web 40 is bonded to the elastic film 30
such that it forms a mirror image of the nonwoven web 20 relative to the
elastic film 30. As such, it can be advantageous (although not required)
for each of the nonwoven webs 20 and 40 to be made of the same material
and to include the same arrangement of layers in order to simplify the
manufacturing process of the stretchable laminate.

[0076]In one embodiment, any of the previously discussed nonwoven layers
120, 1120, 2120, 320, 140, 1140, 2140 and 340 of spunbond fibers can
comprise or be made of bi-component fibers made of two polyolefin
polymers having different melt temperatures and different tensile
properties. In one embodiment, each of the two polyolefin polymers used
to form the bi-component fibers are substantially non-elastic.
Bi-component fibers may have any configuration known in the art but it is
believed that bi-component fibers 50 as represented in FIG. 4 having a
core 150 distinct from a sheath 250 may be advantageous in particular
when the core 150 comprises a first polymer having a first melt
temperature and the sheath 250 comprises a second polymer having a second
melt temperature that is lower than melt temperature of the first
polymer. In one embodiment, the melt temperature of the first polymer
forming the core is at least 130° C., at least 140° C. or
even at least 150° C. The melt temperature of the second polymer
forming the sheath is less than 150° C., less than 140° C.
or even less than 130° C. The melt temperature of a polymer may be
determined according to ASTM D 3418. In one embodiment, the first polymer
forming the core may have a density of at least 0.9 g/cc, at least 0.92
g/cc or at least 0.95 g/cc. The second polymer forming the sheath may
have a density of less than 0.95 g/cc, less than 0.92 g/cc or less than
0.9 g/cc. The density of a polymer may be determined according to ASTM D
792.

[0077]A process line 60 that may be used to manufacture a nonwoven web
including two layers of bi-component spunbond fibers, two layers of
meltblown fibers and one layer of spunbond fibers is schematically
represented in FIG. 5. The process line includes a first beam 160 that is
adapted to produce bi-component spunbond fibers, a second beam 260 and a
third beam 360 that are adapted to produce meltblown fibers and fourth
and fifth beams 460, 560 that are adapted to produce bi-component
spunbond fibers. Each of the beams 160, 460 and 560 that are used to
produce bi-component fibers may be connected to a pair of extruder (not
shown) that feed the respective polymers (forming the core and the sheath
of the fibers) to spinnerets of the beams as it is well know in the art.
It will be appreciated that various spinneret configurations may be used
to obtain different bi- or multicomponent fibers. The bi-component
spunbond fibers that are produced by the first beam 160 are deposited on
a forming surface 660 which can be a foraminous belt. The forming surface
660 may be connected to a vacuum in order to draw the fibers onto the
forming surface. The meltblown fibers that are produced by the second
beam 260 are then deposited onto the first layer of bi-component spunbond
fibers. The fibers of each subsequent beam are deposited onto the layer
formed by the preceding beam. The resulting web of five layers may then
be thermo point bonded with a pair of rollers 760 as it is well know in
the art. It will also be appreciated that the number, the order of the
beams and the type of fibers produced by each beam may be adjusted as
needed to produce a desired multi-layers nonwoven web. When meltblown
fibers are laid onto a first (or even a second) layer of spunbond fibers,
some of the meltblown fibers are deposited into the interstices formed by
the much larger spunbond fibers and some fibers are even able to reach
the side of the spunbond layer that is resting on top of the forming
surface through these interstices. When such an SMS includes at least a
layer of spunbond bi-component fibers having a sheath made for example of
polyethylene and at least a layer of meltblown fibers made for example of
polypropylene, it is observed that the meltblown fibers extending through
the interstices of the first layer of spunbond fibers (i.e. the layer
laid directly on the forming surface) may easily be removed when this
side of the nonwoven SMS web is rubbed against another surface. The
removal of these fibers may result in various problems depending on which
side of the SMS is ultimately the most likely to be subject to rubbing
against another surface. For example, an adhesive may be applied directly
onto one of the sides of an SMS web in order to bond the SMS web to
another web. One suitable process to apply an adhesive directly onto the
web is slot coating. In a slot coating process, a side of a web is moved
against a die which includes one or more openings through which a molten
hotmelt adhesive is delivered. The molten hotmelt adhesive can cause the
die to reach a relatively elevated temperature which can at least soften
or even melt the polyethylene sheath of the spunbond fibers. In addition,
the continuous rubbing of the nonwoven web against the die can cause the
meltblown fibers protruding through the interstices of the first spunbond
layer to break and to accumulate against the die when the exterior
surface of this layer is rubbed against the die. This accumulation of
meltblown polypropylene fibers in combination with the presence of soften
or even molten polyethylene can lead to frequent interruptions of the
manufacturing process (in order to clean the die) and waste of material.
It will be appreciated that such an issue may not occur when the fibers
forming the meltblown layer and the sheath of the bi-component fibers
forming the spunbond layer include a similar polymer such as a
polypropylene. When a slot coating process is used, it can therefore be
advantageous to apply an adhesive directly on the exterior facing surface
of the spunbond layer that has been formed last during the web
manufacturing process (i.e. the layer that includes no or very little
meltblown fibers protruding through interstices of a spunbond layer). In
another embodiment, a hotmelt adhesive having a lower melt and
application temperature may be used to help lower the temperature of the
die during the slot coating process. Lowering the temperature of the die
below the melt temperature of polyethylene used to make the sheath of the
bi-component fibers, reduces the chances that the polyethylene sheath may
melt during the slot coating process. In an alternative embodiment, a
high or low melt temperature adhesive may be applied on the exterior
facing surface of either the first or last spunbond layer formed during
the web manufacturing process, via a direct (i.e. direct contact between
the application tool and the web surface) but low-rubbing application
process. By "low-rubbing application process," it is meant a process
where at least a portion of the application and the web are in motion
during application of the adhesive in order to minimize the rubbing of
the web against the application tool. One example of such a process
include printing the adhesive onto the web with gravure roll as disclosed
in U.S. Pat. No. 6,531,025 to Lender et al., issued Mar. 11, 2003 and
assigned to The Procter & Gamble Company. In yet another embodiment, a
high or low melt temperature adhesive may be applied on the exterior
facing surface of either the first or last spunbond layer formed during
the web manufacturing process, via an indirect (i.e. no direct contact
between the application tool and the web surface) application process. A
suitable example of such a process includes spraying the adhesive onto
the web.

[0078]As previously discussed, at least one of the layers (that include
bi-component fibers) of a nonwoven web may be adhesively bonded to the
elastomeric web with for example a hotmelt adhesive. In one embodiment, a
hotmelt adhesive is applied directly onto the nonwoven web at a
temperature that is less than the melt temperature of the polymer that
forms the sheath of the bi-component fibers. In one embodiment, a hotmelt
adhesive is applied in a molten/liquid phase at a temperature of less
than 150° C., less than 140° C. or even less than
130° C. such that the molten adhesive does not cause the polymer
that forms the sheath of the fibers to melt significantly. Non-limiting
examples of hotmelt adhesive that can be applied in a molten/liquid phase
at such temperatures are disclosed in US Patent Application Publication
No. 2007/0088116 to Abba et al. filed Oct. 14, 2005, published Apr. 19,
2007, and assigned to Bostik, Inc. 11320 Watertown Plank Road, Wauwatosa,
Wis. 53226. However, it may also be advantageous to apply an adhesive
indirectly to the nonwoven web (i.e. without direct contact of the
application tool against the nonwoven web) at a temperature that is
higher than the melt temperature of the polymer forming the sheath as
long as the temperature of the adhesive is less than the melt temperature
of the polymer forming the sheath of the fibers once the adhesive reaches
the fibers of the web. It is believed that under such conditions, the
adhesive does not cause the sheath of the fibers to melt significantly.
In an alternative embodiment, it may be advantageous to apply an adhesive
onto the nonwoven web at a temperature that is higher than the melt
temperature of the polymer forming the sheath of the bi-component fibers.
The adhesive may be applied at temperature of at least 130° C., at
least 140° C. or even at least 150° C. Non-limiting
examples of such hotmelt adhesive include ZEROCREEP that is available
from Bostik. It is believed that when a hotmelt adhesive is applied to
the nonwoven at a temperature that is higher than the melt temperature of
the polymer forming the sheath of the bi-component fibers, the sheath may
melt and increase the number of bonds between individual fibers and
between the fibers and the skin layer of an elastomeric web especially
when the composition of the skin layer comprises is substantial the same
as the composition of the polymer forming the sheath. In one embodiment,
any of the layers of spunbond fibers previously discussed in the context
of a nonwoven web 20 and/or 40, may comprise bi-component fibers of the
core/sheath type such that the core of these fibers comprises a
polypropylene polymer and the sheath of these fibers comprises a
polyethylene polymer. Nonwoven webs are typically thermo point bonded to
provide the web with enough integrity to be rolled and further processed
at a later time. One suitable example of a thermo point bonding process
includes calendering using calender rolls with a bonding pattern. During
the calendering process, bonds are formed on or through the web by
locally applying pressure and heat to cause the polymer of the fibers to
flow within the bond region. However, it is believed that the calendering
temperature of any of the previously described nonwoven webs that
includes a layer of spunbond bi-component fibers should be greater than
the melt temperature of the polymer forming the sheath of the fibers but
that it should also be lower than the melt temperature of the polymer
forming the core of those fibers. It is believed that a calendering
temperature greater than the melt temperature of both the polymers
forming the bi-component fibers may have an adverse impact on the tensile
properties of the nonwoven web in particular when the nonwoven web
includes core/sheath type bi-component fibers. It is believed that when
the calendering temperature of a bi-component fiber web is greater than
the melt temperature of both the polymers forming the bi-component
fibers, these fibers are weakened in the vicinity of the thermo-bonds and
that, as a result, such a nonwoven web may be more prone to localize
tearing during mechanical activation which may also result in the elastic
film being torn as well. In one embodiment, any of the nonwoven webs
disclosed herein that include bi-component fibers are thermo point bonded
at between 110° C. and 140° C., between 115° C. and
135° C. or even between 120° C. and 130° C. In
contrast, when the calendering temperature of a bi-component fiber web is
less than the melt temperature of the polymer forming the core but is
higher than the melt temperature of the polymer forming the sheath of the
bi-component fibers, the core of these fibers maintain a sufficient level
of strength which allows the web to elongate to a greater extent with a
reduced chance of catastrophic failure of the nonwoven web during
mechanical activation of a laminate. FIGS. 6 through 11 are pictures of
two nonwoven webs and are taken with an electron microscope. FIG. 6 is a
picture of a spunbond/meltblown/spunbond nonwoven web whose fibers are
made of a mono-component polypropylene and that has been calendered at a
temperature higher than the melt temperature of the polypropylene used to
make the fibers of the web. The nonwoven web of FIG. 6 is bonded to an
elastic film that is not visible on this picture. Three bond sites are
visible on this picture. FIG. 7 is a picture of the same nonwoven web of
FIG. 6 in an area of the web that has been mechanically activated. Four
bond sites are at least partially visible on this picture. The left side
of the picture includes two bond sites that have been strained during
mechanical activation of the laminate. Several of the spunbond fibers
have "popped out" of the bond site they were part of prior to mechanical
activation as can be seen in FIG. 8 which is a magnified picture of one
of the bond sites shown in FIG. 7. Some of these fibers have even been
broken during mechanical activation. FIG. 9 is a picture of a
spunbond/meltblown/spunbond nonwoven web whose fibers are made of
polypropylene/polyethylene bi-component fibers of the core/sheath type
that has been calendered at a temperature higher than the melt
temperature of the polyethylene but lower than the melt temperature of
the polypropylene used to make the fibers of the spunbond layers. The
nonwoven web of FIG. 9 is bonded to an elastic film that is not visible
on this picture. FIG. 10 is a picture of the same
spunbond/meltblown/spunbond nonwoven web as in FIG. 9 in an area of the
nonwoven web that has been subjected to mechanical activation. The
elastic film of the laminate is at least partially visible in the left
portion of the picture. Although the bond sites visible in FIG. 10 appear
to have been deformed or strained during mechanical action, very few of
the bi-component spunbond fibers have "popped out" of the bond sites. In
addition, very few of these fibers appear to have been broken during
mechanical activation. FIG. 11 is a magnified picture of one of the bond
sites of the nonwoven web of FIG. 10. The molten polyethylene sheath is
at least partially visible in this picture. It should be noted that the
nonwoven web represented in FIGS. 6 through 8 is disposed on one side of
an elastic film and that the nonwoven web represented in FIGS. 9 through
11 is disposed on the other side of the elastic film to form a
stretchable laminate.

[0079]To further illustrate the benefit of a nonwoven web that includes
layers of spunbond bi-component fibers in comparison to a nonwoven web
that includes layers of spunbond mono-component fiber, the tensile curve
of different samples of nonwoven webs is measured in the cross-machine
direction of the webs.

[0080]Pre-Activation Tensile Test:

[0081]A first tensile test that is intended to mimic the behavior of a
nonwoven web during mechanical activation in the CD direction of a
laminate is performed on several nonwoven webs. This test is done
following EDANA method 20.2-89 with the following changes. A specimen
measuring 10 mm (along the CD of the web) by 25 mm (along the MD of the
web) of a given nonwoven web is delicately cut from the web. The tensile
curve of this specimen is obtained by gripping the edges parallel to the
Machine Direction of the specimen with clamps connected to a tensile
tester such as a tester from MTS. The gauge length (i.e. clamp to clamp
separation) is approximately 5 mm. The tensile curve is obtained at a
cross-head displacement speed of approximately 2 mm/s. In order to
minimize the influence of the basis weight of each web sample being
tested, each curve is normalized for the basis weight of the sample being
tested (i.e. the values of the force applied are divided by the value of
the aggregate basis weight of the web sample being tested). The
elongation of each sample is reported on the x axis in percent elongation
while the force applied to each sample is reported on the y axis in
Newton per centimeter grams (N.m2/g.cm). The specimen is pulled
until it ruptures (i.e. the post peak force response reaches a value less
than 10% of the peak force). Results of the tensile tests are represented
in FIG. 12.

[0082]The tensile curve indicated by Roman numeral I is obtained on a
nonwoven web made of carded staple fibers having an average diameter of
18.4 microns and having an aggregate basis weight of 27 g/m2. Such a
carded nonwoven web is commercially available from Albis Germany Nonwoven
GmbH, Aschersleben DE. The tensile curve indicated by Roman numeral II is
obtained on a SMMS nonwoven web made of mono-component polypropylene
fibers and having an aggregate basis weight of 17 g/m2. The fibers
of the first and second spunbond layers have an average diameter of 19
microns and each have a basis weight basis weight of 7.25 g/m2. The
fibers of each of the two layers meltblown layers of this web have an
average diameter of 2.4 microns and each meltblown layer has a basis
weight of 1.25 g/m2. Such a SMMS nonwoven web is commercially
available from Fibertex, from Aalborg Denmark. The tensile curve
indicated by Roman numeral III is obtained on a SSMMS nonwoven web whose
spunbond layers are made of bi-component polypropylene/polyethylene
fibers of the core/sheath type and having an aggregate basis weight of 20
g/m2. The fibers of each of the layers of spunbond bi-component
fibers have an average diameter of 19.0 microns and each of these layers
has a basis weight of 6 g/m2. The ratio of polypropylene to
polyethylene of the bi-component fibers is approximately 70/30 by weight.
The fibers of each of the two layers meltblown fibers of this web have an
average diameter of 2.6 microns and each meltblown layer has a basis
weight of 1 g/m2. This SSMMS nonwoven web is provided by Pegas
Nonwovens s.r.o., Znojmo CZ. The tensile curve indicated by Roman numeral
IV is obtained on a SSMMS nonwoven web whose spunbond layers are made of
bi-component polypropylene/polyethylene fibers of the core/sheath type
and having an aggregate basis weight of 20 g/m2. The fibers of each
of the layers of spunbond bi-component fibers have an average diameter of
20.0 microns and each of these layers has a basis weight of 6 g/m2.
The ratio of polypropylene to polyethylene of the bi-component fibers is
approximately 70/30. The fibers of each of the two layers meltblown
layers of this web have an average diameter of 2.6 microns and each
meltblown layer has a basis weight of 1 g/m2. This SSMMS nonwoven
web is provided by Pegas. The tensile curve of the carded nonwoven web
indicates that this web does not require a lot of force to be elongated
(the maximum force peaks at approximately 6.6 10E-2 Nm2/gcm for an
elongation of approximately 250% in the sample tested) and it maintains
most of its integrity even at a high elongation (the sample tested is
able to elongate 900% its original length). The SMMS nonwoven web that
includes mono-component fibers of polypropylene requires a much greater
amount of force to be elongated (the maximum force peaks at approximately
22 10E-2 Nm2/gcm for an elongation of approximately 100% in the
sample tested) and rapidly deteriorates (the sample tested is not able to
sustain an elongation greater than about 330%). In contrast, the nonwoven
webs that include layers of bi-component fibers maintain their integrity
well past the maximum elongation obtained on a nonwoven web made of
mono-component fibers. The maximum force applied to first of these
nonwoven webs (that includes layers of bi-component spunbond fibers and
is identified by Roman numeral III) peaks at approximately 18.5 10E-2
Nm2/gcm for an elongation of approximately 180% and this nonwoven
web maintains most of its integrity even when it is elongated to
approximately 500% of its original length. The maximum force applied to
the second of these nonwoven webs (that also includes layers of
bi-component spunbond fibers and is identified by Roman numeral IV) peaks
at approximately 13 10E-2 Nm2/gcm for an elongation of approximately
270% and this nonwoven web maintains most of its integrity even when
elongated to approximately 700% of its original length. In one
embodiment, a stretchable laminate can include a nonwoven web that
includes spunbond fibers which may be bi-component fibers as previously
discussed, and which has a resistance to elongation of at least 5 10E-2
Nm2/gcm, at least 7.5 10E-2 Nm2/gcm or even 1 10E-1
Nm2/gcm when a sample of this nonwoven web is elongated to 300% of
its original length. In one embodiment, a stretchable laminate can
include a nonwoven web that includes spunbond fibers which may be
bi-component fibers as previously discussed, and which has a resistance
to elongation of at least 5 10E-2 Nm2/gcm when a sample of this
nonwoven web is elongated to 300%, 400% or even 500% of its original
length. It is believed that a nonwoven web having at least one of the
previous characteristics is able to sustain mechanical activation in
particular when a plurality of the portions of the stretchable laminate
are subjected to an elongation higher than 300%.

[0083]It is observed that the tensile responses or curves of each of the
nonwoven web samples all include a pre-activation maximum peak force
(hereinafter "PA-MPF") or load after which the nonwoven webs start
degrading or deteriorating. It is believed that the rate or "speed" at
which a sample nonwoven web deteriorates after it has reached its PA-MPF
may be a good indicator of the nonwoven web performance when bonded to an
elastic film to form a stretchable laminate. One suitable way to
determine the deterioration rate of a nonwoven web is to measure the
slope of a straight line that connects the PA-MPF point on the curve to
the point on the tensile curve representing a decrease in strain of
approximately 30% after the PA-MPF. The absolute value of this slope is
calculated in order to obtain a positive value. These lines are
represented with dashed lines on FIG. 12 for the reader's convenience.
The deterioration rate after a decrease in strain of approximately 30%
(herein after Dr30% of the nonwoven web made of carded staple fibers
(indicated by Roman numeral I) is equal to approximately

One of ordinary skill will appreciate that a nonwoven web having a
relatively high Dr30% value may tend to deteriorate rapidly after
the web has been strained or elongated past its PA-MPF. Conversely, a
nonwoven web having a relatively low Dr30% value may tend to
maintain its integrity after the web has been strained or elongated past
its PA-MPF. In one embodiment, a stretchable laminate includes an elastic
film and at least a nonwoven web bonded to one side of this film and
which comprises at least one layer of spunbond fibers, preferably
bi-component fibers, having a Dr30% of less than 10 10E-2. This
nonwoven web may also have a Dr30% of less than 8 10E-2, less than 6
10E-2, or even less than 5 10E-2. In one embodiment, it may be
advantageous for this nonwoven web to have a Dr30% of between 1
10E-2 and 10 10E-2, between 2 10E-2 and 8 10E-2, or even between 3 10E-2
and 6 10E-2, It is worth noting that although the aggregate basis weight
of the nonwoven webs that include bi-component spunbond fiber (indicated
by Roman numerals III and IV) is higher than the basis weight of the
nonwoven web that is made of mono-component spunbond fibers, their PA-MPF
is surprisingly lower than the PA-MPF of the nonwoven web that is made of
mono-component spunbond fibers. It is also worth noticing that the
nonwoven webs that include bi-component spunbond fibers reach their
respective PA-MPF at a significantly higher elongation than the
elongation obtained when the nonwoven web made of mono-component spunbond
fibers reaches its own PA-MPF.

[0084]In order to confirm the benefit of a nonwoven web comprising the
spunbond bi-component fibers previously described, two different examples
of stretchable laminates are made and activated. A first stretchable
laminate is made and comprises a first nonwoven web layer similar to the
one previously discussed and identified by Roman numeral I that is bonded
to one side of an elastic film and a second nonwoven web similar to the
one previously discussed and identified by Roman numeral II is bonded to
the other side of the elastic film. Both nonwoven webs are bonded to the
film with a hotmelt adhesive. A second stretchable laminate is also made
and comprises a first nonwoven web layer similar to the one previously
discussed and identified by Roman numeral II that is bonded to one side
of an elastic film and a second nonwoven web similar to the one
previously discussed and identified by Roman numeral III is bonded to the
other side of the elastic film. Both nonwoven webs are bonded to the film
with a hotmelt adhesive. All of the layers used to make the first and
second examples of stretchable laminates have a Machine Direction equal
or greater than 25 mm and a Cross Machine Direction equal or greater than
75 mm. A central portion that includes the film layer and measuring
approximately 40 mm of each of the stretchable laminates is mechanically
activated by passing this 40 mm central portion between a pair of
pressure applicators having three-dimensional surfaces which at least to
a degree are complementary to one another at a Depth of Engagement of
approximately 6 mm. A more detailed description of a suitable mechanical
activation process is provided below. It should be noted that these two
stretchable laminates are subjected to the same amount or level of
mechanical activation. A laminate specimen measuring 75 mm (along the CD
of the laminate) by 25 mm (along the MD of the laminate) of each of the
laminate examples is cut such that the 40 mm central region that has
previously been activated is centered on each laminate specimen. The
nonwoven webs on each side of the stretchable laminate specimen are then
removed from the elastic film by first soaking the specimen into acetone
for about 15 seconds in order to dissolve the adhesive and then
delicately remove the nonwoven web from the elastic film. In the event
the adhesive does not dissolve any other solvent that can dissolve the
adhesive without significantly damaging the nonwoven web can be used.
Once the delaminated nonwoven web is removed from the film, the specimen
should be left to dry for approximately 30 minutes before further
testing. FIGS. 13A-13B are pictures (taken on a dark background for
clarity) showing one example of the elastic film and each of the nonwoven
webs after the webs are removed from the film. It can be observed in the
pictures shown in FIGS. 13A and 13E that the nonwoven webs that include
layers of mono-component spunbond fibers are visibly torn in the areas of
the web that have been subjected to mechanical activation. In contrast,
it can be observed that although the nonwoven web made of carded staple
fibers (FIG. 13D) and the nonwoven web that includes layers of
bi-component spunbond fibers (FIG. 13B) are highly elongated, the areas
that are subjected to mechanical activation are not torn and many fibers
are present in the portions that are mechanically activated. FIG. 13 is a
picture of a typical film after removal of the nonwoven webs. The tensile
curve of these mechanically activated nonwoven webs (removed from the
elastic film) is measured in order to determine whether these
mechanically activated nonwoven webs may still oppose further elongation.
The tensile curve of each nonwoven web specimen is obtained under a
different tensile test that is intended to mimic actual use of the
laminate. This second test is done following EDANA method 20.2-89 with
the following changes. Each specimen measures 75 mm (along the CD of the
web) by 25 mm (along the MD of the web) and the tensile curve of the
specimen is obtained by gripping the edges parallel to the Machine
Direction of the specimen with clamps connected to a tensile tester such
as a tester from MTS. The gauge length (i.e. clamp to clamp separation)
is approximately 70 mm. The tensile curve is obtained at a cross-head
displacement speed of approximately 2 mm/s. The elongation of each
specimen is reported on the x axis in percent elongation while the force
applied to each sample is reported on the y axis in Newton per centimeter
(N/cm). The specimen is pulled until it ruptures (i.e. the post peak
force response reaches a value less than 10% of the peak force). The
tensile curve of each of these mechanically activated nonwoven webs is
represented in FIG. 14. The tensile curve indicated by Roman numeral V is
obtained for a SSMMS web that includes bi-component fibers and is
delaminated from a mono-component SMMS/elastic film/SSMMS laminate. The
tensile curve indicated by Roman numeral VI is obtained for a web of
carded staple fibers and is delaminated from a mono-component
SMMS/elastic film/Carded web laminate. The tensile curve indicated by
Roman numeral VII is obtained for a SMMS web that is made of
mono-component fibers and is delaminated from a mono-component
SMMS/elastic film/Carded web laminate. The tensile curve indicated by
Roman numeral VIII is obtained for a SMMS web that is made of
mono-component fibers and is delaminated from a mono-component
SMMS/elastic film/SSMMS laminate. One possible way to characterize such
nonwoven webs after removal from the stretchable laminate is to determine
their Residual Maximum Peak Force (hereinafter "R-MPF"). By "Residual
Maximum Peak Force" it is meant the maximum peak force of at least one of
the nonwoven webs used to form a stretchable laminate after at least a
portion of the stretchable laminate is activated. It can be observed that
the nonwoven webs that include layers of mono-component spunbond fibers
oppose very little resistance to elongation. The R-MPF of the
mono-component SMS web indicated by Roman numeral VII is less than
approximately 0.15 N/cm and the R-MPF of the mono-component SMS web
indicated by Roman numeral VIII is less than approximately 0.1 N/cm. The
R-MPF of the nonwoven web that includes bi-component fibers and is
indicated by Roman numeral V is at least approximately 0.6 N/cm while the
R-MPF of the mono-component carded web indicated by Roman numeral VI is
at least approximately 0.45 N/cm. It is believed that these results
confirm that these nonwoven webs have been significantly torn or shredded
during mechanical activation of the stretchable laminate. In contrast,
the nonwoven webs made of carded staple fibers and the nonwoven web that
includes layers of bi-component spunbond fibers are still able to resist
elongation and contribute to the strength of the stretchable laminate. It
can be advantageous for any of the previously described stretchable
laminate to include a nonwoven web comprising bi-component spunbond
fibers such that this nonwoven spunbond web has a R-MPF of at least 0.3
N/cm, at least 0.4 N/cm or even at least 0.5 N/cm. It may also be
advantageous for any of the previously described stretchable laminate to
include a nonwoven web comprising bi-component spunbond fibers such that
this nonwoven spunbond web has a R-MPF of less than 2.5 N/cm, less than 2
N/cm, less than 1.5 N/cm or even less than 1 N/cm. It is believed that a
nonwoven web that has bi-component spunbond fibers (preferably of the
core/sheath type) is capable of enduring mechanical activation at a
higher depth of engagement and/or a higher speed than a nonwoven web that
is made exclusively of mono-component fibers. As a result, a stretchable
laminate including such a nonwoven web and an elastic film having a given
basis weight and tensile properties may also be activated to a higher
level. In the alternative, a stretchable laminate including such a
nonwoven web with bi-component fibers and an elastic film having a
reduced basis weight and/or tensile properties may be activated to
substantially the same level as a stretchable laminate having a nonwoven
web made of mono-component fibers and an elastic film having a greater
basis weight and/or tensile properties.

[0085]As further discussed below, any of the previously described
stretchable laminates may be used as components of disposable absorbent
articles (for example diapers or pants) that may include stretchable ears
or side panels. Disposable absorbent articles that are commercially
available include stretchable ears or side panels which are made from a
stretchable laminate comprising nonwoven webs made of mono-component
fibers. It is typical for a caregiver or a user to elongate the ears or
side panel from 85% to 125% of the ear or side panel original length. It
is believed that an elongation from 85% to 125% of the stretchable
element' original length, provides adequate fit and comfort to the
wearer. However, it is also believed that some caregivers and users may
(knowingly or unknowingly) elongate these stretchable elements well above
125% of the element's original length. Such a high elongation may result
in the wearer feeling some discomfort but it may also result in the
tearing of stretchable element which, in turn, renders the absorbent
article unusable. It is believed that these drawbacks may be minimized in
not eliminated by providing a stretchable element made of any of the
previously described stretchable laminates (that include a nonwoven web
with bi-component fibers) that can signal to the caregiver or the user
that the stretchable element should not be elongated any further. This
signal may be provided by way of a stretchable laminate whose resistance
to elongation increases noticeably when the stretchable element is
elongated more than 100% of its original relaxed length. FIG. 15
represents the tensile curves that are obtained for two different
stretchable laminates. The first stretchable laminate (indicated by Roman
numeral IX) includes a nonwoven SMMS web made of mono-component fibers
(having an aggregate basis weight of 17 g/m2), an elastic film
(having a basis weight of 54.5 GSM) which is a coextruded film having
styrene block copolymer elastomeric core and polyolefin skin, and a web
of carded mono-component fibers (having a basis weight of 27 g/m2).
The second stretchable laminate (indicated by Roman numeral X) includes a
nonwoven SMMS web made of mono-component fibers (having an aggregate
basis weight of 17 g/m2), an elastic film (having a basis weight of
54.5 g/m2) similar to the one previously discussed and a SSMMS web
that includes bi-component spunbond fibers (having an aggregate basis
weight of 20 g/m2). It can be observed that these tensile curves are
substantially identical up to an elongation of 80% of the laminate's
original length. It can also be observed that the force required to
elongate the stretchable laminate that has a SSMMS web that includes
bi-component spunbond fibers is greater than the force required to
elongate the stretchable laminate that has a web of carded mono-component
fibers when the stretchable laminates are elongated more than 85% of
their respective original length. The difference between the amount of
force required to elongate both laminates (herein after "ΔF")
can be as high as approximately 0.5 N/cm at an elongation from 110% to
160% of the stretchable laminates original length. It is believed that a
caregiver or a user may start noticing this increased resistance to
elongation when he or she attempts to elongate the stretchable element
(including several cm2 of the stretchable laminate) of an article
beyond 85% of the stretchable element original length. It is also
believed that an increased resistance to elongation may communicate to
the caregiver or user that the stretchable element should not be
elongated any further. It is further believed that the residual
resistance to elongation of a web (in particular in a web including
bi-component fibers) after the laminate is mechanically activated,
provides the increased resistance to elongation that occurs when the
stretchable laminate is elongated more than 85% of its original length.
It can be advantageous for any of the previously described stretchable
laminate to include a nonwoven web that comprises bi-component spunbond
fibers and that is such that the force required to elongate this web
after mechanical activation of stretchable laminate at an elongation of
between 85% and 125% is between 0.2 N/cm and 1.5 N/cm, between 0.3 N/cm
and 1.2 N/cm or even between 0.4 N/cm and 1 N/cm. It is believed that a
nonwoven web that has bi-component spunbond fibers (preferably of the
core/sheath type) can conveniently be used to make a stretchable laminate
that will provide a noticeable resistance to elongation when a
stretchable element made of this stretchable material is elongated more
than 85% of its original length.

[0086]Mechanical Activation of a Laminate:

[0087]Any of the previously discussed stretchable laminate can be
mechanically activated (i.e. pre-strained) such that the laminate
recovers some of the elasticity it lost when all the webs forming the
laminate are bonded together. A non-limiting example of a process for
mechanically activating a stretchable laminate is schematically
represented in FIGS. 16 and 17. The device shown in those figures include
a pair of pressure applicators 34, 36 having three-dimensional surfaces
which at least to a degree are complementary to one another. A pressure
applicator (or roler) includes at least one engaging portion or tooth 134
(but may also include a plurality) corresponding to a recess portion 136
of the other pressure applicator. A pressure applicator preferably
includes a plurality of engaging portions or teeth 134 and recess
portions 234 that can intermesh with a corresponding recess portions 136
and engaging portions or teeth 236 on the other pressure applicator. When
the laminate passes in between the pressure applicators 34, 36, portions
of the laminate are strained. The stretchable laminate is able to relax
and return substantially to its original width as it "exits" the pressure
applicators. The degree of mechanical activation may be adjusted by
varying the number of engaging portions and recess portions and the depth
of engagement of the pressure applicators on the stretchable laminate.
One of ordinary skill in the art will appreciate that other processes for
mechanically activating a stretchable laminate may be used and still
provide the same benefits.

[0088]With reference to FIG. 17, which shows a portion of the intermeshing
of the engaging portions 134 and 236 of pressure applicators 34 and 36,
respectively, the term "pitch" refers to the distance between the apexes
of adjacent engaging portions. The pitch can be between approximately
0.02 to approximately 0.30 inches (0.51-7.62 mm), and is preferably
between approximately 0.05 and approximately 0.15 inches (1.27-3.81 mm).
The height (or depth) of the teeth is measured from the base of the tooth
to the apex of the tooth, and is preferably equal for all teeth. The
height of the teeth can be between approximately 0.10 inches (2.54 mm)
and 0.90 inches (22.9 mm), and is preferably approximately 0.25 inches
(6.35 mm) and 0.50 inches (12.7 mm). The engaging portions 134 in one
pressure applicator can be offset by one-half the pitch from the engaging
portions 236 in the other pressure applicator, such that the engaging
portions of one pressure applicator (e.g., engaging portion 134) mesh in
the recess portions 136 (or valleys) located between engaging portions in
the corresponding pressure applicator. The offset permits intermeshing of
the two pressure applicators when the pressure applicators are "engaged"
or in an intermeshing, operative position relative to one another. In one
embodiment, the engaging portions of the respective pressure applicators
are only partially intermeshing. The degree to which the engaging
portions on the opposing pressure applicators intermesh is referred to
herein as the "depth of engagement" or "DOE" of the engaging portions. As
shown in FIG. 17, the DOE is the distance between a position designated
by plane P1 where the apexes of the engaging portions on the respective
pressure applicators are in the same plane (0% engagement) to a position
designated by plane P2 where the apexes of the engaging portions of one
pressure applicators extend inward beyond the plane P1 toward the recess
portions on the opposing pressure applicator. The optimum or effective
DOE for particular laminates is dependent upon the height and the pitch
of the engaging portions and the materials of the web. In other
embodiments the teeth of the mating rolls need not be aligned with the
valleys of the opposing rolls. That is, the teeth may be out of phase
with the valleys to some degree, ranging from slightly offset to greatly
offset.

[0089]A laminate including any of the webs previously discussed may be
adapted for use in a disposable absorbent article such as a diaper, a
pant, an adult incontinence product a sanitary napkin or any other
article that may benefit for having at least a portion thereon that is
elastically stretchable. In one embodiment, ears or side panels may be
cut from such a stretchable laminate and one side edge of the ear may be
attached to the chassis of a disposable absorbent article. A disposable
absorbent article 70 that include a back waist region 170, a crotch
region 270 and a front waist region 370 is schematically represented in
FIG. 18. A pair of ears 75 are attached along their respective proximal
edge to the left and right sides of the disposable absorbent article
respectively. A fastener such as a mechanical comprising a plurality of
extending hooks or an adhesive may be connected to a portion of the ear
or side panel about the distal edge of the ear or side panel. Such a
fastener may in combination with the laminate stretchability provide for
proper placement and attachment of the absorbent article about the lower
torso of a wearer. In another embodiment, any such laminate may be used
as an integral outer cover for an absorbent article. A typical chassis of
a disposable absorbent article 70 may include a liquid pervious top sheet
470, a liquid impervious backsheet 570 and an absorbent core 670 disposed
between the topsheet and the backsheet and are schematically represented
in FIG. 19. An absorbent article may also include any features that may
be suitable for such an article and are known in the art.

[0090]The dimensions and values disclosed herein are not to be understood
as being strictly limited to the exact numerical values recited. Instead,
unless otherwise specified, each such dimension is intended to mean both
the recited value and a functionally equivalent range surrounding that
value. For example, a dimension disclosed as "40 mm" is intended to mean
"about 40 mm". Every document cited herein, including any cross
referenced or related patent or application, is hereby incorporated
herein by reference in its entirety unless expressly excluded or
otherwise limited. The citation of any document is not an admission that
it is prior art with respect to any invention disclosed or claimed herein
or that it alone, or in any combination with any other reference or
references, teaches, suggests or discloses any such invention. Further,
to the extent that any meaning or definition of a term in this document
conflicts with any meaning or definition of the same term in a document
incorporated by reference, the meaning or definition assigned to that
term in this document shall govern.

[0091]While particular embodiments of the present invention have been
illustrated and described, it would be obvious to those skilled in the
art that various other changes and modifications can be made without
departing from the spirit and scope of the invention. It is therefore
intended to cover in the appended claims all such changes and
modifications that are within the scope of this invention